Duplicating machine



Oct. 28, 1941. w. A. KROPP DUPLICATING MACHINE Filed May 31, 1940 4 Sheets-Sheet 1 Nil I I INVENTOR. [Z/LZZA? 01K r950,

ATTORNEY.

Oct. 28, 1941. w, KRQPP DUPLICATING' MACHINE Filed May 51, 1940 4 Sheets- Sheet 2 Oct. 28, 1941. w. A. KROPP DUPLICATING MACHINE Filed May 51, 1940 m 3 N INVENTOR. Q. ffro a M ATTOR JEY.

Q ZL LZZLS Oct. 28, 1941. w KROPP DUPLICATING. MACHINE Filed May 31, 1940 4 Sheets-Sheet 4 I INVENTOR. BY ZZ/LZZLa CZ. r0 2 Patented Oct. 28, 1941 UNITED STATES PATrem OFFICE Willis A. Kropp,

Victor Adding River Forest, 111., assignor to Machine Company, Chicago, 111.,

a corporation of Illinois Application May 31, 1940, Serial No. 338,100 12 Claims. (01. ion-132) This invention relates to improvements in duplicating machines and in particular to the mechanisms for driving rotary drums and for feeding copy sheets so as to assure accurate registration of the copy sheets with the master copies.

One of the objects of the invention is to provide a novel driving mechanism for a rotary duplicating drum which will intermittently rotate the drum between positions at which copy sheets are fed to the drum.

Another object of the invention is to provide in a duplicating machine a margin stop on the drum of the machine and'a mechanism for causing the drum to stop rotating to permit a copy sheet to be fed to the margin stop, while the primary driving means for the drum continues to rotate.

Another object of the invention is to provide gearless means for intermittently rotating a duplicating drum combined with a continuously operating driving means therefor.

Another object of the invention is to provide an automatic feed of copy sheets to a margin stop on an intermittently driven duplicating drum.

Various other objects and advantages of the invention will be described specifically or will become apparent from a perusal of this specification.

In the drawings, Fig. l is a sectional view on the line l--I of Fig. 3 of a machine made in accordance with my invention.

Fig. 2 is another sectional view on the line 2-2 of Fig. 3.

Fig. 3 is a view partly in elevation and partly in section along the irregular line 3-3 of Fig. 2.

Fig. 4 is a side elevation of the machine as viewed from the right side thereof.

Referring further to the drawings, the machine is provided with a base consisting of longitudinal members I and 2 and transverse members 3 and 4 connected rigidly together to form a rigid base. To the cross members are attached suitable feet, any one of which may be designated as 5. Side frame plates 6 and 1 are secured to the longitudinal base members and support between them the drum and other operative portions of the mechanism.

The drum itself is generally cylindrical, being formed of a sheet of metal 8 secured to end walls 9 and II, the longitudinal edges of the sheet of metal being bent inwardly at the flanges l2 and I3, thereby leaving a gap of considerablearcuate Width extending the full length of the drumbe- 55 t tween its end walls. On this drum a duplicating handmade of gelatin or some other suitable material may be positioned.-

When a gelatin band is employed, it will ordinarily-have a hook member M which maybe engaged over the edge of the flange l3, while the other end of the band will be provided with a similar hook member to be engaged by a tensioning device. The latter is in the form of a plate I 5 secured to a rod 1 6 which is pivotally mounted in the opposite end walls of the drum. Rigidly connected with the rod and plate- I5 for rotating the same is another rod I! connected by rigid arms to the rod l6, one of these arms being indicated as I8 in Fig. 1. Formed integrally with each of the arms l8 at opposite ends of the rod [6 'are depending flanges such as l9 to which may be connected springs such as 2| secured to the inside surfaces of the drum end walls for normally rotating the duplicating band tensioning device into the interior of the drum.

To attach the duplicating band to the drum, the channel-shaped hook I4 on one end of the band is engaged over the flange l3. The band is then carried around the drum and the tensioning member is grasped by the handle rod [1, rotated outwardly from the drum gap against the action of springs 2| far enough so that the hook 22 on the other end of the band may be engaged over the plate I5. The springs will then be permitted to rotate the tensioning device back toward its normal position, the band tautly over the drum surface.

The duplicating drum itself is carried on a shaft 23 which is journalled in'bearings 24 and 25 supported in the side frame plates 6 and 1. The operatingv handle '26 is rigidly secured to the right-hand end of the shaft 23. If amotor drive should be employed, it could be connected to the shaft in place of the handle.

Referring to Fig. 3, the drum end wall 9 is secured by means of rivets to a gear 21 and also to a bushing 28, the latter riding freely on the shaft 23, so that the drum and shaft are free to rotate relatively to each other. The gear 21 is employed to drive a gear 29 secured to the shaft 3| of a rubberstripping roll 32.

V The opposite end Wall of the drum is supported on bushing 33 in which the. drum shaft is free to rotate. A plate 34 is fixed on the bushing 33 against the enlarged portion 35 of the bushing, the plate or disk 34 being screwed, riveted or welded to the drum end wall. Between the bearing 25 in which the shaft rotates and the'bushing 33 and its enlarged portion 35,

thereby stretching which are shaped to provide between the outer margin of plate 42 and the inner margin of plate 41, a cam groove which is employed in the interrupted drive of the duplicating cylinder.

Cooperating With the cam plates 4| and 42 is a bell crank pivotally mounted in the cam disk 31 on the pivotal axis 43 and comprising a pair of bell crank arms 44 and 45, the latter arm carrying a cam follower 46 pivotally mounted, on the arm on ball bearings and engaged in the cam groove between the plates 4| and 42. The other bell' crank arm 44 pivotally carries a square head '41 which is adapted for sliding QQYement in a rectangular slot 48in the plate 34. The cam disk 3'! which is non-rotatably mounted on the shaft 23 by means of the keyed bushing 36 drives the bell crank and the bell crank drives the drum through the arm 44 and plate 34. However, when the shaft 23 is being rotated manually or by motive power at a uniform speed, .6. speed of rotation of the drum will be varied in accordance with the motions of the bell crank induced by the cam follower 46. If the cam follower 46 traveled in a perfectly circular cam way concentric with the axis of the drum shaft, the

drum and shaft would always move at the same speed. While the shaft is rotating at a uniform speed. and consequently the pivotal axis 43 is moving at the same uniform speed, whenever the camfollower 46 tends to approach the axis of the shaft the opposite end of the bell crank will be rotated in a direction counter to the direction of rotation of the shaft, thereby retarding the s eed of rotation of the drum. Conversely with the, cam follower and receding. from the shaft axis, the square head carried by the opposite end of the bell crank will accelerate the drum relativelyv to, the shaft. Accordingly, the cam'way formed by the plates 41 and 42 is so designed" that in a portion of the cam way the deceleration of the drum caused by the radially inward movement of the. cam follower 46 is caused to offset the; forward. motion of the bell crank axis 43,- whereby for a shorttime during the rotation of shaft 23, the drum will be standing still.

The cam way and the bell crank are so designed andpositioned relatively to each other that .thedrum is caused to stop while the shaft continuesto rotate when the-partsv are occupying-the position shown in Fig. 1, at which time itwill be ,noted that the margin bar. 49 has been rotated to a position underneath the pressure roller '51, the. feeding position for copy sheets. Accordingto the'design shown, after the drum has been rotated to bring. the margin bar to the position shown. in Fig. l, the drum shaft can be rotated in the neighborhood of an additional 50 before the drum will resume rotating. This interval is ample time for the sheet feeding mechanism. or a manual feeding operation to feed a copysheetsnugly up. against the margin bar as. shown in Fig. 1. i

It will now be apparent that the length of the interval may be varied by a change of design of. thee-am and the cooperating parts. In fact since. the inward rotation of the bell crank arm 15 tends to .'rotate. the. drum 'rear'wardly while;

the forward movement of the pivotal axis 43 tends to rotate the drum forwardly, it is possible to have the effect of the inward movement of the arm 45 greater so that the drum could be rotated rearwardly a short distance. Also, the parts could be so designed that the effect of the inward movement of the bell crank arm 45 would not quite offset the forward propelling effect of the motion of the pivotal axis 43. Hence, the design could be so arranged as to cause the drum to move forwardly at all times but slowly for part of the revolution. It will be perceived that when the arm 45 is swinging radially outwardly and the bell crank axis 43 is moving at a uniform speed, the drum will be propelled by the bell crank at a higher rate of speed than the shaft is then rotating.

Normally, this mechanical movement is useful in temporarily stopping the drum in the duplicating machine herein shown, but it may be used for a similar purpose or for generally varying the relative speeds between the drive'means and the drum in any duplicating machine, 7

The margin bar heretofore referred to, I is mounted on a pivoted deflector plate generally indicated as 52 supported on a rod 53 journaled in the drum end Walls. An extension 54 from the flange l3 forms an anchor for a spring '55 which may be connected to a downwardly extending center leg 56 on the deflector plate, tending normally to rotate the edge portion 51 of the deflector plate outwardly a slight distance beyond the peripheral surface of the drum, excepting when the deflector is held down by the pressure roller 51'. The extent to which this deflector may rotate outwardly is limited by the contact of a'leg 58 depending from deflector 52 with a bumper 58 provided on a plate 59 likewise pivoted: on the rod 53. The extent to which the pressure roller may press the deflector 52 in-. wardly is limited by contact of a leg 60 depending from deflector 52 with an' eccentrically pivoted adjustable button 66. A spring 6| connected ;to. the opposite end of the plate 59 and anchored on the inside surface of the adjoining drum and wall tends normally to hold the plate 59. against an eccentrically pivoted adjustable button 63;. I

a To; attach the end of a gelatin band to or remove it from the flange I3, one needs only to press on the center leg 56., causing leg 58 topress on. the bumper 58' to 'rotate the whole unit including the plate '59 farenough to provide a large ap between the edge of the deflector'andthe shoulder of the flange l3. To, advance. copy sheets. from a stack on the feed table 64, there is provided'a feed-mechanism consisting of an armJ'G5 pivoted on a post 66 carried by the side frame plate and provided at its'opposite end with a follower 6.1. which follows the cam 3:1 A linkcomprising two members 68 and; 69; the latter carrying a. post if and theformer, a post 12 connected by. a tension spring 13; orms, a resiliently extensible link'for transmitting cam. motion to a. bell crank 14' fixed'on a. red 15; onwhich isfixed another duplicate bell crank, thetwo of which operate'a friction feed-e ing shoe 1-61fixed on the end ofian arm 1T piv.-. otally mounted on a cross rod 18 carried. at the upper ends of the pair. of bell. cranks. Asxthe high-point: on, the cam 31 is reached; as shown inyEig. 1:, the feeding shoe islmoved forwardly by the-:pair of bell cranks and friction'ally engages the top :sheetonl the stack to" slide' it underneath the."guide;-plate Hlupagainsti the. margin bar 49'.

Continued'rotation of the shaft-23 by 'means o'f theha'ndle126 or by motive power will eventually move the marginibar' 49 out'from underneath the pressure roller whereupon thelatter will press the'copy sheet first against the deflector plate 52.and thereafter. againstthe duplicating band 8| to receive the'copy' therefrom. I I,

The stripping of a copysheet is accomplished as follows. After the deflector. plate passes from underneath the pressure 'roller, itwwill be deflected a short distance outwardly .by the springs 55 causing the overlying edgefof the copy sheet likewise to be deflected outwardly from the periphery of the drum. Astl'iis deflected portion comes around to ,the. position of the stripping plate .82, it willbe engaged thereby and caused to "pass between .theyrubber roller 32 and another roller, preferably a knurled metalroller v83. The latter rollercmay bean idler, whereas the rubber roller. 32"is 'positivelydriven by the gear 21, The sheet will thereby be stripped from the duplicating band, guided by the plate 84 and dropped intothe delivery chute 85 with the printed side up.

V The pressure roller 5|" heretofore mentioned, is mounted on a shaft carried between a pair of arms 86 and8'lxpivoted. at,.88 and 89, the arms being held downwardly-by springs, one of which is shown in.Fig. 4 and isnumbered 9|. The idling stripping roll83 is likewise carried on a shaft journaled in a :pair of arms 92 and 93 mounted outside of themain side frame plates, each arm being'held' under tension by springs such as 94. Any other suitable means for supplying adjustable pressure on these two rollers may be employed.

The feed table herein illustrated is provided with adjustable side plates such as 95 and 96 through which may protrude elements such as pads for engaging the sides of the stack of copy sheets.

In the operation of the device, the handle may be continuously operated, the drum stopping, as explained heretofore, for a short interval with the margin bar underneath the pressure roller. 5|. At this time, the automatic feeding mechanism will advance a copy sheet with its leading edge against the margin bar, or this may be done manually, Further rotation of the handle will cause the drum to resume rotating, after which the copy sheet will be pressed against the duplicating band and subsequently stripped as heretofore explained.

It should be understood that the embodiment herein shown and described, is merely illustrative of one form of the invention and that other forms and modifications of the whole and its parts may be devised and employed without de- 4 parting from the spirit and scope of the invention, particularly as it may be defined in the appended claims.

Having shown and described my invention, I claim:

1. In combination with a duplicating machine having a rotary master copy drum, a mechanism for imparting intermittent rotary motion to the drum comprising a continuously rotating driving member, an element pivotally connected with said member and driven thereby through the pivot, one end of said element being connected to the drum for driving the same, and. means for rotating the element about its pivotal axis during the circular travel of said axis whereby during a portion of said travel no rotative motion will be imparted to said drum,

"f 2. .In a duplicating machine, a rotary'fmaster copy drum, a'ro'tary driving member, a driving element pivotally mounted'on' said member at a position spaced from the axis of said member, means connecting onetend' portion of said member with the drum to thereby impart rotary motion toxthe drum, and means'for rotating said element about its pivotal axis'while said axis is continuously moving in a circular path for varying the relative rotative speed of said drum and said driving member. i

3. In'a duplicating machine, a rotary master copy drum, a rotary'driving member, a driving element pivotally mounted on said member at a position spaced from the axis of said member, means connecting one. endportion of said member with the drum to "thereby impart rotary'mo tion'to .the drum, and means for rotating said element'about its pivotal axis while the latter is continuously: moving in a circular path for varying the. speed of the drum relatively to that of the driving member from equality to. zero 4. In combination with a duplicating machine having a rotary'master copy drum, an intermittent driving mechanism therefore comprising a continuously rotating driving member, an element pivotally carried by said member and having its pivotal axis moving continuously through a circular path, means connecting saidelement with the drum for driving the latter, and means operating during the continuous movement of said pivotal axis torotate said element about its pivotal axis in'a direction opposed to the rotation of said driving member whereby for an interval no rotative movement is imparted to the drum.

5. In a duplicating machine having a rotary master copy drum, a rotary driving member, a pivoted element driven by said driving member, one end of said pivoted element being operatively connected to the drum for rotating the same, a cam, and the other end of said element being arranged to follow said cam to rotate said pivoted element about its axis to thereby vary the relative rotative speeds of the drum and said driving member.

6. In a duplicating machine having a rotary drum for carrying master copies, means for driving the drum including a continuously rotating driving member, an element pivotally carried by said member, one end of said pivoted element being operatively connected to the drum for driving the same, and a cam, the other end of said element being controlled by said cam for rotating the whole element on its pivotal axis for varying the speed of rotation of the drum relatively to the driving member.

7. A duplicating machine having a rotary master copy drum and a copy sheet margin stop carried by the drum, and a driving mechanism for intermittently rotating the drum and stopping it with the margin stop at the feeding position comprising a continuously rotatable primary driving member, an element pivotally carried bygsaid member and pivoted between its ends, one end of said element having an operative connection with the drum to transmit rotated movement thereto, and means acting on the other end of said element for rotating said Operative connection about the pivotal axis of the element in opposition to the travel of said pivotal axis for intermittently stopping the drum,

intermittently rotating the drum and stopping it l with the margin stop at the feeding position c'omprising 'a continuously rotatable primary driving member, an element pivotally carried by said member and. pivoted between its end s,: one .end 1 of said element havingan operative connection 1 with the drum to transmit rotative movement 1 thereto; means acting on the other end of said element. for rotating said operative connection about the pivotal axis of the element in opposition to the travel of said pivotal axis for intermittently stopping the'drum,'and means actuated by the rotation of said driving mechanism arranged to automatically feed the copy sheets to said margin stop when the drum is stationary.

9. In a duplicating machine having a rotary master copy drum, a rotary shaft, a rotary member driven by said-shaft, an element pivoted between its ends on said member to rotate bodily therewith, an operative connection between one,

end of said element and the drum for rotating the latter, and stationary cam means cooperating with the other end of said element for rotating'said elementabout its pivotal support to varyv thereby the relative rotative speeds of the drum and said shaft.

10. In a duplicating machine having a rotary master copy drum, a rotary shaft, a rotary member driven by saidshaft, an element pivoted between i'ts ends on said member to rotate bodily,

therewith, an operativefconnectionbetween one end of said element and the .drum for rotating the latter, and stationary cam means cooperating with the otherendof said element for rotat v ing said element/about its pivotal support to vary thereby the relative ,rotative speeds of the. drum and. said shaft, said cam and element being con:- structed and arranged to cause the drum to stop at the copy sheet feeding position during part of the continuousqrotation of the shaft. I

' 11.'In a duplicating machine, a rotary master copy drum, a drive; shaft, an arm fixed on said shaft torotate concentrically therewith, an element pivotally supported between its ends on said arm at av point spaced apart from the axis of rotation of said arm, means slidably connecting one end of said element with the drum for rotating the latter, means for oscillating said end of said element about its pivotal aXis during ro= tation of the shaft to vary the relative speed of rotation of the shaft; and drum. v

'12. In a duplicating machine, a rotary drum, a continuously rotating shaft concentric with the drum, an element pivotally carried by said memb'erfand continuously driven at its pivotal point along with said-shaft, one portion of said element being operatively connected with the drum to propel the same, a cam follower on another portion of said element, means providing a stationary cam, way, cooperating with said follower to pivotallyrotate. said element to hold the drum stationary during a. portion of the rotation of said shaft, and means for feeding copy sheets to the drum for accurate registration therewith while the drum is stopped, a I

. I I 'VVILLIS A. KROPP. 

